Shaped microcomponents via reactive conversion of synthetic microtemplates

ABSTRACT

The purpose of the present invention is to describe a novel approach for converting 3-dimensional, synthetic micro- and nano-templates into different materials with a retention of shape/dimensions and morphological features. The ultimate objective of this approach is to mass-produce micro- and nano-templates of tailored shapes through the use of synthetic or man-made micropreforms, and then chemical conversion of such templates by controlled chemical reactions into near net-shaped, micro- and nano-components of desired compositions. The basic idea of this invention is to obtain a synthetic microtemplate with a desired shape and with desired surface features, and then to convert the microtemplate into a different material through the use of chemical reactions.

[0001] This application claims the benefit of U.S. Provisional PatentApplication No. 60/314,533, filed on Aug. 23, 2001, which isincorporated herein by reference.

TECHNICAL FIELD OF THE INVENTION

[0002] The present invention is in the field of shaped microcomponentsor micropreforms fabricated via the reactive conversion of syntheticmicrotemplates. These synthetic microtemplates or micropreforms may thenbe converted into other oxides by a chemical reaction(s).

BACKGROUND OF THE INVENTION

[0003] The worldwide research and development effort on microdevices(e.g., electromechanical, hydromechanical, thermomechanical,electrochemical, thermoelectrical, etc.) has increased dramatically overthe past decade. Such devices have found significant use as sensors inautomotive and medical applications, with estimates of the global MEMS(microelectromechanical systems) market ranging from $12-14 billion in2000. However, a far larger untapped potential exists for the use of newmicromechanical devices in a variety of advanced applications, such asin: i) medicine (e.g., targeted drug or radiation delivery, rapidclinical and genomic analyses, in vitro sensors, microtools for surgery,micropumps and microvalves, microreactors, etc.), ii) transportation andenergy production (e.g., new sensors and actuators for pollutioncontrol, enhanced energy utilization, and improved engine performance;microcomponents for automotive, diesel, jet, or rocket engines;microcomponents for turbines used in energy conversion or generation;microreactors, micropumps, microbearings, etc.), iii) communications andcomputing (e.g., micro-optical devices, microactuators, microswitches,microtransducers, etc.), and iv) the production/manufacturing of food,chemicals, and materials (e.g., microrobotics, rapid on-linemicrosensors, microreactors, micropumps, microdies, etc.).

[0004] Despite the recognized technological and economic significance ofnew microdevices, the fabrication methods used to date have been largelylimited to techniques developed within the microelectronics industry.The micromachining of silicon may be done by one or a combination ofmethods, including but not limited to: photolithography (e.g. UV, x-ray,e-beam, ion-beam), dry physical etching (e.g. ion etching/sputtering,laser ablation), dry chemical etching (e.g. with a reactive gas),combined dry physical and chemical etching (e.g. reaction ion etching),wet chemical etching and LIGA. Furthermore, the properties of silicon(room temperature brittleness, poor creep resistance at □600° C., highthermal conductivity, modest melting point, biochemical incompatibility,etc.) make silicon-based microdevices unattractive for a number ofpotential applications. New fabrication methods capable of yieldingself-assembled, non-silicon microdevices in a massively parallel fashionare needed to allow for a much wider range of commercial applications.

[0005] The purpose of the present invention is to provide a novelapproach for converting 2- or 3-dimensional, synthetic(non-naturally-occurring) micro- and nano-templates into new materialswith a retention of shape/dimensions and morphological features. Theultimate objective of this approach is to mass-produce micro- andnano-templates of tailored shapes through the use of synthetic orman-made micropreforms, and then chemical conversion of such templatesby controlled chemical reactions into near net-shaped, micro- andnano-components of desired compositions.

SUMMARY OF THE INVENTION

[0006] The basic idea of this invention is to obtain a synthetic(non-naturally-occurring) microtemplate with a desired shape and/or withdesired surface features, such as through micromachining of a material,and to convert the microtemplate into a different material with shapemaintenance through the use of chemical reactions. For example, siliconmay be micromachined to obtain a silicon micropreform. The siliconmicropreform may then be oxidized (for example by heating in dry or wetoxygen or air) to obtain a silica microtemplate, or the siliconmicropreform is used as a template or mold onto which silica or a silicaprecursor is deposited by any of the known deposition methods. Thesilica microtemplates may then be converted into a another oxide oroxide/metal composite through chemical reaction(s).

[0007] Another method of obtaining a microcomponent of the presentinvention is to micromachine silicon and then use the resulting siliconmicropreform to obtain a shaped silicon-bearing ceramic precursorcompound (e.g., SiC, Si3N4, MoSi2). The fabrication of a silicon-bearingceramic precursor compound micropreform from a shaped siliconmicropreform may be conducted by gas phase reaction of the shapedsilicon micropreform (e.g., nitridation of the patterned siliconmicropreform, carburization of the patterned silicon micropreform,reaction of patterned silicon with a Mo-bearing gas to form MoSi2), orby using the shaped or patterned silicon micropreform as a template ormold onto which a silicon-bearing compound or a silicon-bearingprecursor compound may be deposited. Then the silicon-bearing precursorcompound micropreforms may be converted into other oxides or oxide/metalcomposites through chemical reaction(s). The silicon-bearing ceramicprecursor compounds may themselves be useful compounds or they may beconverted to ceramics or intermetallic compounds.

[0008] The present invention is to a method for the production of shapedmicrocomponents comprising the steps of: obtaining at least onesynthetic microtemplate having an original chemical composition and anoriginal dimensional feature; and subjecting the at least one syntheticmicrotemplate to a chemical reaction, so as to partially or completelyconvert the microtemplate into a microcomponent having a chemicalcomposition different than the original chemical composition and havingsubstantially the same dimensional feature(s) as the original syntheticmicrotemplate.

[0009] The reacted or changed microtemplate may possess a composition, ashape, and surface features appropriate for a particular microcomponentor microdevice (e.g., microsprings, microball bearings, microsyringes,etc.). Other medical microdevices in which the present invention may beused are fully discussed in U.S. Pat. No. 6,107,102 to Ferrari, U.S.Pat. No. 6,044,981 to Chu et al., U.S. Pat. No. 5,985,328 to Chu et al.,U.S. Pat. No. 5,985,164 to Chu et al., U.S. Pat. No. 5,948,255 to Kelleret al., U.S. Pat. No. 5,893,974 to Keller et al., U.S. Pat. No.5,798,042 to Chu et al., U.S. Pat. No. 5,770,076 to Chu et al., and U.S.Pat. No. 5,651,900 to Keller et al. The above-listed patents are herebyincorporated by reference. Hence, by this novel combined use ofmicromachining and reaction engineering, a large number ofmicrocomponents of desired shape and of desired composition may beproduced.

[0010] “Micromachining” of silicon may be done by one or a combinationof methods, including but not limited to: photolithography (e.g. UV,x-ray, e-beam, ion-beam), dry physical etching (e.g. ionetching/sputtering, laser ablation), dry chemical etching (e.g. with areactive gas), combined dry physical and chemical etching (e.g. reactionion etching), wet chemical etching and LIGA.

[0011] “Deposition” is meant to include physical or chemical vapordeposition, spin coating of a silica slurry or silica precursorsolution, screen printing of silica slurry or silica precursor solution,pressing of hot viscous glass onto the silicon micropreform, and castingof molten glass onto the silicon micropreform.

[0012] A “dimensional feature” is meant to include a shape or a surfacefeature. Surface features include, but are not limited to, pores,spacings between pores, depressions, ridges, and protuberances.

[0013] The terms “microtemplate”, “micropreform” or “microarticle” arehereby used interchangeably and are deemed to have the same meaning.Zeolites are compounds that may be included in the definition ofmicroporous or nanoporous preforms.

[0014] The term “patterned silicon” or “patterned silicon micropreform”means a silicon that has been formed into a specific shape or amicropreform that has been previously shaped.

[0015] A “microcomponent” is defined as an object that may have at leastone size dimension that is less than 1 millimeter and is preferably lessthan 100 microns and most preferably less than 25 microns and/or atleast one surface feature with a dimension that is less than 1millimeter and is preferably less than 100 microns and most preferablyless than 25 microns.

[0016] The chemical reaction used to partially or completely convert thesynthetic microtemplate may be an additive reaction in which a reactantis chemically incorporated as a compound, solid solution, or mixturewith the original constituents of the microtemplate. Such additivereactions are of the general type:

aA_(b)Y_(c)+M_(d)X_(e)=>aA_(b)Y_(c).M_(d)X_(e)  (1)

[0017] where A_(b)Y_(c) is a reactant, M_(d)X_(e) is a constituent ofthe microtemplate, and aA_(b)Y_(c).M_(d)X_(e) is the ionically orcovalently bonded new solid compound, solid solution, or solid mixtureobtained from this reaction that is retained in the microcomponent; andwherein a, b, c, d, and e are any stoichiometric coefficients. M isdefined as any metal cation, X is defined as a metalloid ion. Thereactant, A_(b)Y_(c), involved in this additive reaction may be presentas a gas, a liquid or as a solid or within a gas phase, within a liquidphase or within a solid phase during the reaction. The reactant,A_(b)Y_(c), may also be deposited onto the microtemplate as a solid orliquid phase and then allowed to react, while in the solid or liquidstate, with the microtemplate. An example of an additive reaction is:

nP_(x)O_(y)(g)+3CaCO₃(s)=>3CaO.nP_(x)O_(y)(s)+3CO₂(g)  (2)

[0018] where P_(x)O_(y)(g) is a gaseous phosphorus oxide reactantspecies, CaCO₃(s) is a solid constituent of a microtemplate, and3CaO.nP_(x)O_(y)(s) is the solid product of this additive reaction thatis retained in the microcomponent.

[0019] The chemical reaction used to partially or completely convert thesynthetic microtemplate may be a metathetic (exchange) reaction of thefollowing type:

aA_(b)X_(w)+M_(c)X_(y).N_(d)X_(z)=>aA_(b)X_(w).N_(d)X_(z)+M_(c)X_(y)  (3)

[0020] in which “a” moles of reactant A_(b)X_(w) react with one mole ofM_(c)X_(y).N_(d)X_(z) present within the microtemplate. In thismetathetic reaction, the “a” moles of reactant A_(b)X_(w) exchange withone mole of M_(c)X_(y) in the compound M_(c)X_(y).N_(d)X_(z) to form theionically or covalently bonded products aA_(b)X_(w).N_(dX) _(z) andM_(c)X_(y). The product aA_(b)X_(w).N_(d)X_(z) may be a solid compound,a solid solution, or a solid mixture. The reactant, A_(b)X_(w), involvedin this metathetic reaction may be present as or within a gas phase or aliquid phase during the reaction. The reactant, A_(b)X_(w), may also bedeposited onto the microtemplate as a solid or liquid phase and thenallowed to react, while in the solid or liquid state, with themicrotemplate. A, M and N are all defined as any metal cation. X is ametalloid ion. a, b, c, d, w, y and z are any stoichiometriccoefficients.

[0021] The chemical reaction used to partially or completely convert thesynthetic microtemplate may be an oxidation-reduction (redox) reactionof the following type:

yA+aM_(x)O_(y)=>yAO_(a)+axM  (4)

[0022] in which “y” moles of elemental reactant A react with “a” molesof the oxide M_(x)O_(y) present within the microtemplate. In this redoxreaction, “y” moles of the reactant A become oxidized to form “y” molesof the product oxide, AO_(a), and M within the oxide, M_(x)O_(y), isreduced to form “ax” moles of M. A is defined as any elemental reactantbut is preferably an element having a metallic characteristic. M is anymetal. a, x and y are any stoichiometric coefficients. The elementalreactant, A, involved in this oxidation-reduction reaction may bepresent as or within a gas phase or a liquid phase during the reaction.The elemental reactant, A, may also be deposited onto the microtemplateas a solid or liquid phase and then allowed to react, while in the solidor liquid state, with the microtemplate. A redox reaction may be used toexchange the silicon in silicon oxide (silica) with a displacingreactant species, so as to convert the silicon oxide into a differentmetal oxide compound. An example of such a redox reaction is:

2Mg(g)+SiO₂(s)=>2MgO(s)+Si(s)  (5)

[0023] where Mg(g) is a gaseous displacing reactant species, SiO₂(s)(silica) is a solid oxide constituent of a microtemplate, and MgO(s) isthe solid oxide product of this redox reaction that is retained in themicrocomponent. In this example, Mg(g) is the displacing reactantspecies that is oxidized to form MgO and SiO₂(s) is reduced to formSi(s). In this example, the displacing reactant species may be anyreactant species adapted to reduce the silicon oxide into silicon. Forinstance, the said displacing reactant species may be selected from thegroup consisting of alkaline earth elements, such as beryllium,magnesium, calcium, strontium, barium, and mixtures thereof. The saiddisplacing reactant species may also be selected from the groupconsisting of alkali elements, such as hydrogen, lithium, and mixturesthereof. The said displacing reactant species may also be selected fromthe group consisting of aluminum, titanium, zirconium, hafnium, yttrium,lanthanum, cerium, praesodymium, neodymium, samarium, europium,gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium,lutetium, thorium, uranium, and mixtures thereof.

[0024] The microcomponent may define a space wherein the space isprovided with at least one additional non-native substance. The at leastone additional non-native substance may be a pharmaceutically activesubstance. The non-native substance may have an avenue of escape fromthe defined microcomponent space, whether by exiting through microporesor by osmosis.

[0025] The present invention is also to a method for the production of ashaped microcomponent comprising the steps of: obtaining at least onesynthetic microtemplate having an original chemical composition, and anoriginal dimensional feature; and subjecting the at least one syntheticmicrotemplate to a first chemical reaction, so as to partially orcompletely convert the at least one synthetic microtemplate into anintermediate microcomponent having a second chemical compositiondifferent than the original chemical composition; and then subjectingthe intermediate microcomponent to a second chemical reaction so as topartially or completely convert the intermediate microcomponent into theshaped microcomponent having a chemical composition different than theoriginal chemical composition and different than the second chemicalcomposition and having substantially the same dimensional feature as theoriginal dimensional feature.

[0026] Among the reactions that may be used to convert silica-basedmicrotemplates into other oxides or oxide/metal composites aresolid/fluid displacement (oxidation-reduction) reactions of thefollowing type:

SiO₂(s)+2/yM(g)=>2/yMO_(y)(s)+(Si)  (6)

SiO₂(S)+2/yM(l)=>2/yMO_(y)(s)+(Si)  (7)

[0027] where (Si) refers to silicon present as a pure solid, liquid, orgas or to silicon dissolved in a solid, liquid, or gas solution. Forexample, prior work has shown that silica (SiO₂(s)) may be convertedinto Al₂O₃/Al—Si composites that retain the shape/dimensions within 1%by the following net reaction:

3SiO₂(s)+4Al(l)=>2Al₂O₃(s)+3(Si)  (8)

[0028] where (Si) refers to an Al—Si alloy. Exposing silicamicrotemplates to Al-rich liquid alloys may produce such composites. Thesilica may be converted into a dense mixture of Al₂O₃(s) and Al—Si alloywith little (□1%) change in dimensions or shape. That is, although 2moles of Al₂O₃(s) possess a smaller volume than 3 moles of SiO₂(s), thedifference in these volumes is taken up by the liquid Al—Si (and, hence,solid Al—Si upon solidification of this liquid). After such reaction,the excess solidified Al—Si within the transformed silica microtemplatemay be removed by selective etching/dissolution to yield an Al₂O₃(s)body that retains the shape and/or surface features of the startingsilica microtemplate.

[0029] Displacement (oxidation-reduction) reactions of the followingtype may also be used to convert silica-based microtemplates into otheroxides or oxide/metal composites:

2Ca(l)+SiO₂(s)=>2CaO(s)+(Si)  (9)

2Sr(l)+SiO₂(s)=>2SrO(s)+(Si)  (10)

2Ba(l)+SiO₂(s)=>2BaO(s)+(Si)  (11)

[0030] For these reactions, the oxide produced has a larger volume thanthe oxide consumed (e.g., 2 moles of CaO(s) have a larger volume than 1mole of SiO₂(s)). In these cases, although the overall silicamicrotemplate shape may be retained upon reaction, some surface featuresmay be controllably altered (e.g., some of the fine pores of the silicamicrotemplate may be filled in with new ceramic). Alternately, dependingon the reaction conditions, the silica microtemplate may expand uponreaction to yield a larger component with the same shape and withsurface features of the same size. If the (Si) product of reactions(9)-(11) is present as a solid phase, then such silicon may be removedfrom the converted microcomponent (e.g., by selective dissolution), soas to yield microcomponents comprised of only oxides. Pure CaO bodiesmay be particularly attractive for biomedical applications, given thebiocompatibility of CaO in the human body (i.e., CaO may dissolve inblood and be used to enhance natural bone growth).

[0031] In addition to forming single component oxides, reactions may bechosen that yield multicomponent oxides. For example,

Mg₁Al₂(l)+2SiO₂(s)=>MgAl₂O₄(s)+2(Si)  (12)

[0032] Spinel, MgAl₂O₄, is a relatively high melting, refractory oxidewith good resistance to chemical attack by basic or acidic oxide liquidsor by reactive gases (e.g., sodium vapor).

[0033] Reactions may also be chosen that yield multicomponent metalproducts, such as silicides:

X_(4/y)Mo(l)+2SiO₂(s)=>4/yXO_(y)(s)+MoSi₂(s)  (13)

[0034] where X refers to an element capable of undergoing a displacementreaction with SiO₂(s). MoSi₂(s) is a relatively high melting andoxidation-resistant intermetallic compound.

[0035] Oxidation-reduction reactions with silica microtemplates may alsoinvolve gas-phase reactants, such as shown below:

2Mg(g)+SiO₂(s)=>2MgO(s)+(Si)  (14)

2Ca(g)+SiO₂(s)=>2CaO(s)+(Si)  (15)

[0036] By using such gas/solid reactions to transform SiO₂(s), excesssolid metallic reactant (e.g., excess Mg or Ca) adhering to theconverted body may be avoided, unlike for the case of liquid/solidoxidation-reduction reactions. For oxidation-reduction reactionsinvolving a liquid metallic reactant, excess solidified metallicreactant adhering to and surrounding the converted oxide component mustbe removed upon cooling in order to extract the microcomponent. Thisremoval of excess metal is an additional time-consuming step that may beavoided by using gas/solid oxidation-reduction reactions. Hence, suchgas/solid oxidation-reduction reactions have an inherent advantage overliquid/solid oxidation-reduction reactions.

[0037] If the (Si) product of reactions (14) and (15) is present as asolid phase (either pure solid silicon or a silicon-bearing solid), thensuch silicon may be removed from the converted microcomponent (e.g., byselective dissolution), so as to yield microcomponents comprised of onlyoxides. Alternately, a condensed (Si) product phase may be oxidized byreaction with gaseous oxygen to convert the silicon back into SiO₂(s).Subsequent oxide-oxide reactions may then be used to producemicrocomponents comprised of multioxide compounds. For example,reoxidation of a solid (Si) product in reaction (14) to SiO₂(s) followedby the following oxide-oxide reaction may yield a microcomponentcomprised of forsterite, Mg₂SiO₄(s):

2MgO(s)+SiO₂(s)=>Mg₂SiO₄(s)  (16)

[0038] Oxidation-reduction reactions may also be used to partiallyconsume the silica in the microtemplates, so that subsequent oxide-oxidereactions may be used to produce microcomponents comprised of multioxidecompounds. Consider, for example, the following reactions:

2Mg(g)+2SiO₂(s)=>2MgO(s)+SiO₂(S)+(Si)  (17)

3Ca(g)+5/2SiO₂(s)=>3CaO(s)+SiO₂(S)+3/2(Si)  (18)

[0039] In these reactions, the silica is only partially consumed (i.e.,only 1 of 2 moles of silica is reduced by the Mg(g) or Ca(g)). Furtherheat treatment of the oxide products of reactions (17) and (18) in theabsence of gaseous Mg or Ca may result in the formation of therefractory compounds, Mg₂SiO₄ and Ca₃SiO₅, by the following oxide-oxidereactions:

2MgO(s)+SiO₂(s)=>Mg₂SiO₄(s)  (19)

3CaO(s)+SiO₂(s)=>Ca₃SiO₅(s)  (20)

[0040] Oxidation-reduction reactions with silica microtemplates may alsobe used to produce microcomponents comprised of oxide/intermetalliccomposites, such as shown below:

2Mg(g)+SiO₂(S)=>2MgO(s)+Mg₂Si(s)  (21)

2Ca(g)+SiO₂(s)=>2CaO(s)+Ca₂Si(s)  (22)

[0041] A series of reactions may also be used to convert silicamicrotemplates into multicomponent ceramics. For example, silicamicrotemplates may first be converted into CaO by one of the followingoxidation-reduction reactions:

2Ca(l)+SiO₂(s)=>2CaO(s)+(Si)  (23)

2Ca(g))+SiO₂(s)=>2CaO(s)+(Si)  (24)

[0042] After selective removal of the (Si) product (e.g., by selectivedissolution), the resulting, shaped CaO microbodies may then undergofurther reaction(s) to produce shaped microbodies comprised ofCaO-bearing compounds. For example, the following types of additivereactions may be used to convert the CaO into calcium phosphates:

mCaO(s)+nP_(x)O_(y)(g)=>mCaO.nP_(x)O_(y)(s)  (25)

mCaO(s)+nP_(x)O_(y)(g)+pH₂O(g)=>mCaO.nP_(x)O_(y).pH₂O(s)  (26)

[0043] where P_(x)O_(y)(g) refers to a gaseous P-O-bearing species,mCaO.nP_(x)O_(y)(s) refers to a calcium phosphate compound (e.g.,Ca₂P₂O₇, Ca₃P₂O₈), and mCaO.nP_(x)O_(y).pH₂O(s) refers to hydratedcalcium phosphate compounds (e.g., calcium hydroxyapatite,10CaO.6P_(x)O_(y).2H₂O). Calcium phosphate microcomponents may beparticularly attractive for biomedical applications. For example,because calcium hydroxyapatite is the major mineral in human teeth andbones, the body does not reject this compound. Hence calciumhydroxyapatite microcomponents derived from silica microtemplates wouldbe biocompatible. Such biocompatible microcomponents would beparticularly attractive for biomedical applications (e.g., bioresorbablemicrocapsules for targeted drug or radiation delivery).

[0044] The chemical compositions of calcium carbonate microtemplates maybe changed by additive reactions. Such additive reactions may involvegas-phase reactants, as shown below (and mentioned above):

nP_(x)O_(y)(g)+3CaCO₃(s)=>3CaO.nP_(x)O_(y)(s)+3CO₂(g)  (2)

[0045] Alternately, condensed phase reactants may be deposited onto thecalcium carbonate microtemplate by a vapor phase technique (including,but not limited to, sputtering, laser ablation, evaporation, andchemical vapor deposition) or a liquid phase technique (including, butnot limited to, melt infiltration, solution infiltration, slurryinfiltration). After deposition of the reactants, the calcium carbonatemay then undergo an additive reaction with the reactant. Examples ofadditive reactions between condensed phase reactants and calciumcarbonate include, but are not limited to:

6Al₂O₃(s)+CaCO₃(s)=>CaAl₁₂O₁₉(s)+CO₂(g)  (27)

SiO₂(s)+3CaCO₃(s)=>Ca₃SiO₅(s)+3CO₂(g)  (28)

TiO₂(s)+CaCO₃(s)=>CaTiO₃(s)+CO₂(g)  (29)

ZrO₂(s)+CaCO₃(s)=>CaZrO₃(s)+CO₂(g)  (30)

[0046] Metallic precursors to oxide reactants may also deposited ontothe calcium carbonate microtemplate by a vapor phase technique or aliquid phase technique, and then oxidized to form an oxide reactant. Theoxide reactant may then undergo reaction with the calcium carbonate toform a new compound, solid solution, or mixture. Examples of metallicprecursors that may be deposited, oxidized, and then reacted withcalcium carbonate include, but are not limited to phosphorus, aluminum,silicon, titanium, and zirconium (i.e., oxidation of these depositedelements may be followed by reactions with calcium carbonate as perreactions (2) and (27)-(30)).

[0047] Additive reactions of the type (2) and (27)-(30) may also be usedto convert silica microtemplates into silicate compounds. Examples ofsuch additive reactions include, but are not limited to:

3Al₂O₃(s)+2SiO₂(S)=>Al₆Si₂O₁₃(s)  (31)

3CaO(s)+SiO₂(s)=>Ca₃SiO₅(s)  (32)

2MgO(s)+SiO₂(s)=>Mg₂SiO₄(s)  (33)

ZrO₂(s)+SiO₂(s)=>ZrSiO₄(s)  (34)

[0048] Metallic precursors to oxide reactants may also deposited ontothe silica microtemplate by a vapor phase technique or a liquid phasetechnique, and then oxidized to form an oxide reactant. The oxidereactant may then undergo reaction with the silica to form a newcompound, solid solution, or mixture. Examples of metallic precursorsthat may be deposited, oxidized, and then reacted with silica include,but are not limited to aluminum, calcium, magnesium, and zirconium(i.e., oxidation of these deposited elements may be followed byreactions with silica as per reactions (31)-(34)).

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT(S) Embodiment1—Machining/forming Plus Chemical Conversion of Shape to Silica then toDesired Ceramic-bearing Microcomponent

[0049] Silicon is micromachined by one or a combination ofmicromachining methods listed above. The silicon micropreform is thenused to obtain a patterned silica micropreform. The fabrication of asilica micropreform from a patterned silicon micropreform is conductedby oxidation of the patterned silicon micropreform. The silicamicropreform is then used in one or more subsequent chemical reaction(s)or series of reactions to form a ceramic microcomponent that hasmaintained the shape of the original patterned silicon micropreformwhile changing the composition of the micropreform.

Embodiment 2—Machining/forming Plus Coating and Chemical Conversion ofCoating to Silica then to Desired Ceramic-bearing Component

[0050] Silicon is micromachined by one or a combination of micromachinedmethods listed above to yield a silicon micropreform. The siliconmicropreform is then used as a template or mold onto which silica or asilica precursor is deposited by any of the deposition methods listedabove. The silica or silica precursor is then reacted to convert theminto another oxide or oxide/metal composite while maintaining the shapeof the original silicon micropreform.

Embodiment 3—Machining/forming Plus Conversion of Shape toSilicon-bearing Ceramic Precursor Compounds then Conversion to otherCarbides, Nitrides, Silicides and/or to other Ceramics and/or to otherIntermetallic Compounds

[0051] Silicon is micromachined by one or a combination of the methodslisted above to yield a patterned silicon micropreform. The siliconmicropreform is then subjected to a gas phase reaction to yield asilicon-bearing ceramic precursor compound. The silicon-bearing ceramicprecursor compounds are any known silicon based compounds including butnot limited to MoSi₂. The gas phase reactions are for example,nitridation of the patterned silicon micropreform, carburization of thepatterned silicon micropreform, or reaction of the patterned siliconwith a Mo-bearing gas to form MoSi₂. The silicon-bearing ceramicprecursor compounds are themselves useful compounds or may be convertedto other compounds, ceramic compounds or intermetallic compounds.

Embodiment 4—Machining/forming Plus Coating of Silicon-bearing CeramicPrecursor Compounds and then Conversion to other Carbides, Nitrides,Silicides and/or to other Ceramics and/or to other IntermetallicCompounds

[0052] Silicon is micromachined by one or a combination of the methodslisted above to yield a patterned silicon micropreform. The siliconmicropreform is then used as a template or mold onto which a differentsilicon compound (e.g. SiC, Si₃N₄ or MoSi₂) or a silicon compoundprecursor may be deposited by any of the deposition methods listedabove. A chemical reaction then converts deposited materials into othercompounds, ceramic compounds or intermetallic compounds.

Embodiment 5

[0053] Like Embodiment 3 except that carbide, nitride or silicide isfurther converted to a second carbide nitride or silicide, and/or toother second ceramics and/or to other intermetallic compounds.

Embodiment 6

[0054] Like Embodiment 4 except that carbide, nitride or silicide isfurther converted to a second carbide, nitride or silicide, and/or toother second ceramics and/or to other intermetallic compounds.

[0055] The exemplary embodiments herein disclosed are not intended to beexhaustive or to unnecessarily limit the scope of the invention. Theexemplary embodiments were chosen and described in order to explain theprinciples of the present invention so that others skilled in the artmay practice the invention. Having shown and described exemplaryembodiments of the present invention, it will be within the ability ofone of ordinary skill in the art to make alterations or modifications tothe present invention, such as through the substitution of equivalentchemicals or through the use of equivalent process steps, so as to beable to practice the present invention without departing from its spiritas reflected in the appended claims, the text and teaching of which arehereby incorporated by reference herein. It is the intention, therefore,to limit the invention only as indicated by the scope of the claims andequivalents thereof. The claims are hereby incorporated by referencesinto the specification.

What is claimed is: General Method of Making a Ceramic Microarticle
 1. A method for the production of a shaped microcomponent comprising the steps of: a) obtaining at least one synthetic microtemplate having an original chemical composition and an original dimensional feature; and b) subjecting said at least one synthetic microtemplate to a chemical reaction, so as to partially or completely convert the said at least one synthetic microtemplate into said shaped microcomponent having a chemical composition different than said original chemical composition and having substantially the same dimensional feature as said original dimensional feature.
 2. The method of claim 1, wherein said original chemical composition comprises silica.
 3. The method of claim 1, wherein said chemical reaction is a gas phase displacement reaction.
 4. The method of claim 1, wherein said microcomponent template defines a space wherein said space is provided with at least one additional non-native substance.
 5. The method of claim 4, wherein said at least one additional non-native substance is a pharmaceutically acceptable substance.
 6. The method of claim 1, wherein said chemical reaction is an additive reaction of the following type: aA_(b)Y_(c)+M_(d)X_(e)=>aA_(b)Y_(c).M_(d)X_(e) where A_(b)Y_(c) is a reactant, M_(d)X_(e) is a constituent of the said at least one synthetic microtemplate, and aA_(b)Y_(c).M_(d)X_(e) is an ionically or covalently bonded solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent; and wherein a, b, c, d, and e are stoichiometric coefficients.
 7. The method of claim 6 wherein aA_(b)Y_(c).M_(d)X_(e) is selected from the group consisting of solid oxide compounds, oxide solid solutions, and solid oxide mixtures.
 8. The method of claim 6 wherein aA_(b)Y_(c).M_(d)X_(e) is selected from the group consisting of silicon oxide-bearing compounds, silicon oxide-bearing solid solutions, and silicon oxide-bearing mixtures.
 9. The method of claim 6 wherein said silicon oxide-bearing compound is selected from the group consisting of aluminosilicates, alkali silicates, alkaline earth silicates, alkali aluminosilicates, alkaline earth aluminosilicates, borosilicates, cadmium silicates, cobalt silicates, erbium silicates, iron silicates, lead silicates, manganese silicates, neodymium silicates, nickel silicates, yttrium silicates, ytterbium silicates, zinc silicates, zircon, and mixtures thereof.
 10. The method of claim 6 wherein aA_(b)Y_(c).M_(d)X_(e) is selected from the group consisting of calcium oxide-bearing compounds, calcium oxide-bearing solid solutions, and calcium oxide-bearing mixtures.
 11. The method of claim 10 wherein said calcium oxide-bearing compound is selected from the group consisting of calcium alkali-silicates, calcium aluminates, calcium aluminosilicates, calcium alkali-aluminosilicates, calcium bismuthates, calcium borates, calcium cerates, calcium chromites, calcium cuprates, calcium ferrites, calcium gadolinium oxides, calcium gallates, calcium germanates, calcium hafnate, calcium manganates, calcium molybdates, calcium niobates, calcium phosphates, calcium plumbates, calcium silicates, calcium stannates, calcium sulfates, calcium tantalates, calcium titanates, calcium tungstates, calcium uranium oxides, calcium vanadates, calcium yttrium oxides, calcium zirconates, and mixtures thereof.
 12. The method of claim 1, wherein said chemical reaction is a metathetic reaction of the following type: aA_(b)X_(w)+M_(c)X_(y).N_(d)X_(z)=>aA_(b)X_(w).N_(d)X_(z)+M_(c)X_(y) where A_(b)X_(w) is a reactant, M_(c)X_(y).N_(d)X_(z) is a constituent of the said at least one synthetic microtemplate, aA_(b)X_(w).N_(d)X_(z) is an ionically or covalently bonded first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent, and M_(c)X_(y) is a second reaction product; and wherein a, b, c, d, w, y and z are stoichiometric coefficients.
 13. The method of claim 12 wherein aA_(b)X_(w).N_(d)X_(z) is selected from the group consisting of oxide compounds, oxide solid solutions, and oxide mixtures.
 14. The method of claim 12 wherein aA_(b)X_(w).N_(d)X_(z) is selected from the group consisting of silicon oxide-bearing compounds, silicon oxide-bearing solid solutions, and silicon oxide-bearing mixtures.
 15. The method of claim 14 wherein said silicon oxide-bearing compound is selected from the group consisting of aluminosilicates, alkali silicates, alkaline earth silicates, alkali aluminosilicates, alkaline earth aluminosilicates, borosilicates, cadmium silicates, cobalt silicates, erbium silicates, iron silicates, lead silicates, manganese silicates, neodymium silicates, nickel silicates, yttrium silicates, ytterbium silicates, zinc silicates, zircon, and mixtures thereof.
 16. The method of claim 12 wherein aA_(b)X_(w).N_(d)X_(z) is selected from the group consisting of calcium oxide-bearing compounds, calcium oxide-bearing solid solutions, and calcium oxide-bearing mixtures.
 17. The method of claim 16 wherein said calcium oxide-bearing compound is selected from the group consisting of calcium alkalisilicates, calcium aluminates, calcium aluminosilicates, calcium alkalialuminosilicates, calcium bismuthates, calcium borates, calcium cerates, calcium chromites, calcium cuprates, calcium ferrites, calcium gadolinium oxides, calcium gallates, calcium germanates, calcium hafnate, calcium manganates, calcium molybdates, calcium niobates, calcium phosphates, calcium plumbates, calcium silicates, calcium stannates, calcium sulfates, calcium tantalates, calcium titanates, calcium tungstates, calcium uranium oxides, calcium vanadates, calcium yttrium oxides, calcium zirconates, and mixtures thereof.
 18. The method of claim 1, wherein said chemical reaction is an oxidation-reduction reaction of the following type: yA+aM_(x)O_(y)=>yAO_(a)+axM where A is an elemental reactant, M_(x)O_(y) is an oxide constituent of the said at least one synthetic microtemplate, AO_(a) is an oxide first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent, and M is a second reaction product; and wherein a, x and y are stoichiometric coefficients.
 19. The method of claim 18 wherein AO_(a), is selected from the group consisting of solid oxide compounds, oxide solid solutions, and solid oxide mixtures.
 20. The method of claim 18 wherein AO_(a), is selected from the group consisting of silicon oxide-bearing compounds, silicon oxide-bearing solid solutions, and silicon oxide-bearing mixtures.
 21. The method of claim 20 wherein said silicon oxide-bearing compound is selected from the group consisting of aluminosilicates, alkali silicates, alkaline earth silicates, alkali aluminosilicates, alkaline earth aluminosilicates, borosilicates, cadmium silicates, cobalt silicates, erbium silicates, iron silicates, lead silicates, manganese silicates, neodymium silicates, nickel silicates, yttrium silicates, ytterbium silicates, zinc silicates, zircon, and mixtures thereof.
 22. The method of claim 18 wherein AO_(a), is selected from the group consisting of calcium oxide-bearing compounds, calcium oxide-bearing solid solutions, and calcium oxide-bearing mixtures.
 23. The method of claim 22 wherein said calcium oxide-bearing compound is selected from the group consisting of calcium alkali-silicates, calcium aluminates, calcium aluminosilicates, calcium alkali-aluminosilicates, calcium bismuthates, calcium borates, calcium cerates, calcium chromites, calcium cuprates, calcium ferrites, calcium gadolinium oxides, calcium gallates, calcium germanates, calcium hafnate, calcium manganates, calcium molybdates, calcium niobates, calcium phosphates, calcium plumbates, calcium silicates, calcium stannates, calcium sulfates, calcium tantalates, calcium titanates, calcium tungstates, calcium uranium oxides, calcium vanadates, calcium yttrium oxides, calcium zirconates, and mixtures thereof.
 24. The method of claim 18 wherein M, is selected from the group consisting of a solid metal, a solid metal alloy, a solid intermetallic compound, a solid metallic mixture, a solid intermetallic mixture, and mixtures thereof.
 25. The method of claim 1, wherein said chemical reaction involves at least two reactions selected from the group consisting of an additive reaction of the following type: aA_(b)Y_(c)+M_(d)X_(e)=>aA_(b)Y_(c).M_(d)X_(e) where A_(b)Y_(c) is a reactant, M_(d)X_(e) is a constituent of the said at least one synthetic microtemplate, and aA_(b)Y_(c).M_(d)X_(e) is an ionically or covalently bonded solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent; and wherein a, b, c, d, and e are stoichiometric coefficients; a metathetic reaction of the following type: aA_(b)X_(w)+M_(c)X_(y).N_(d)X_(z)=>aA_(b)X_(w).N_(d)X_(z)+M_(c)X_(y) where A_(b)X_(w) is a reactant, M_(c)X_(y).N_(d)X_(z) is a constituent of the said at least one synthetic microtemplate, aA_(b)X_(w).N_(d)X_(z) is a first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent, and M_(c)X_(y) is a second reaction product; and wherein a, b, c, d, w, y and z are stoichiometric coefficients; and an oxidation-reduction reaction of the following type: yA+aM_(x)O_(y)=>yAO_(a)+axM where A is a elemental reactant, M_(x)O_(y) is an oxide constituent of the said at least one synthetic microtemplate, AO_(a) is an oxide first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent, and M is a second reaction product; and wherein a, x and y are stoichiometric coefficients; and combinations thereof.
 26. The method of claim 1, wherein said shaped microcomponent defines a space wherein said space is provided with at least one additional non-native substance.
 27. The method of claim 26, wherein said at least one additional non-native substance is a pharmaceutically active substance.
 28. The method of claim 1 wherein said shaped microcomponent possesses a shape selected from the group consisting of a solid microcylinder, a microtube, a solid microbar, a hollow microbar, a solid microsphere, a hollow microsphere, a microwheel, a microgear, a microrotor, a microplate, a microdisk, a microtetrahedron, a microwedge, a microtetrakaidecahedron, a microspring, a microspiral, a microlever, a microcantilever, a solid microcone, a microfunnel, a microhoneycomb, and a micromesh.
 29. The method of claim 1 wherein said shaped microcomponent is used in a device selected from the group consisting of a micropump, a microvalve, a microfunnel, a micronozzle, a microreactor, a microbearing, a micropulley, a microturbine engine, a micropiston engine, a micromotor, a microactuator, a microswitch, a microtransducer, a microhinge, a microrelay, a microdie, a microsensor, a microcatalyst, a microsyringe, a microneedle, a microcapsule, a microsieve, a microfilter, a micromembrane, a microseparator, a micromirror, a microlens, a microprism, a microdiffraction grating, and a microrefraction grating.
 30. The method of claim 1 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 1 millimeter in size.
 31. The method of claim 1 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 100 microns in size.
 32. The method of claim 1 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 25 microns in size.
 33. The method of claim 1 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 10 microns in size.
 34. The method of claim 1 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 1 micron in size.
 35. The method of claim 1 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 100 nanometers in size.
 36. The method of claim 1 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 25 nanometers in size.
 37. The method of claim 1 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 10 nanometers in size.
 38. A microcomponent made in accordance with the method of claim
 1. 39. A shaped microcomponent made in accordance with claim
 4. General Method Using More than One Chemical Reaction
 40. A method for the production of a shaped microcomponent comprising the steps of: a) obtaining at least one synthetic microtemplate having an original chemical composition, and an original dimensional feature; and b) subjecting said at least one synthetic microtemplate to a first chemical reaction, so as to partially or completely convert said at least one synthetic microtemplate into an intermediate microcomponent having a second chemical composition different than said original chemical composition; and then c) subjecting said intermediate microcomponent to a second chemical reaction so as to partially or completely convert the said intermediate microcomponent into said shaped microcomponent having a chemical composition different than said original chemical composition and different than said second chemical composition and having substantially the same dimensional feature as said original dimensional feature.
 41. The method of claim 40, wherein said original chemical composition is selected from the group consisting of silicon and silica.
 42. The method of claim 40 wherein said first chemical reaction is an additive reaction of the following type: aA_(b)Y_(c)+M_(d)X_(e)=>aA_(b)Y_(c).M_(d)X_(e) where A_(b)Y_(c) is a reactant, M_(d)X_(e) is a constituent of the said at least one synthetic microtemplate, and aA_(b)Y_(c).M_(d)X_(e) is an ionically or covalently bonded solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said intermediate microcomponent; and wherein a, b, c, d, and e are stoichiometric coefficients.
 43. The method of claim 42 wherein aA_(b)Y_(c).M_(d)X_(e) is selected from the group consisting of solid oxide compounds, oxide solid solutions, and solid oxide mixtures.
 44. The method of claim 42 wherein aA_(b)Y_(c).M_(d)X_(e) is selected from the group consisting of silicon oxide-bearing compounds, silicon oxide-bearing solid solutions, and silicon oxide-bearing mixtures.
 45. The method of claim 44 wherein said silicon oxide-bearing compound is selected from the group consisting of aluminosilicates, alkali silicates, alkaline earth silicates, alkali aluminosilicates, alkaline earth aluminosilicates, borosilicates, cadmium silicates, cobalt silicates, erbium silicates, iron silicates, lead silicates, manganese silicates, neodymium silicates, nickel silicates, yttrium silicates, ytterbium silicates, zinc silicates, zircon, and mixtures thereof.
 46. The method of claim 44 wherein aA_(b)Y_(c).M_(d)X_(e) is selected from the group consisting of calcium oxide-bearing compounds, calcium oxide-bearing solid solutions, and calcium oxide-bearing mixtures.
 47. The method of claim 46 wherein said calcium oxide-bearing compound is selected from the group consisting of calcium alkali-silicates, calcium aluminates, calcium aluminosilicates, calcium alkali-aluminosilicates, calcium bismuthates, calcium borates, calcium cerates, calcium chromites, calcium cuprates, calcium ferrites, calcium gadolinium oxides, calcium gallates, calcium germanates, calcium hafnate, calcium manganates, calcium molybdates, calcium niobates, calcium phosphates, calcium plumbates, calcium silicates, calcium stannates, calcium sulfates, calcium tantalates, calcium titanates, calcium tungstates, calcium uranium oxides, calcium vanadates, calcium yttrium oxides, calcium zirconates, and mixtures thereof.
 48. The method of claim 40 wherein said first chemical reaction is a metathetic reaction of the following type: aA_(b)X_(w)+M_(c)X_(y).N_(d)X_(z)=>aA_(b)X_(w).N_(d)X_(z)+M_(c)X_(y) where A_(b)X_(w) is a reactant, M_(c)X_(y).N_(d)X_(z) is a constituent of the said at least one synthetic microtemplate, aA_(b)X_(w).N_(d)X_(z) is an ionically or covalently bonded first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said intermediate microcomponent, and M_(c)X_(y) is a second reaction product; and wherein a, b, c, d, w, y and z are stoichiometric coefficients.
 49. The method of claim 48 wherein aA_(b)X_(w).N_(d)X_(z), is selected from the group consisting of oxide compounds, oxide solid solutions, and oxide mixtures.
 50. The method of claim 48 wherein aA_(b)X_(w).N_(d)X_(z), is selected from the group consisting of silicon oxide-bearing compounds, silicon oxide-bearing solid solutions, and silicon oxide-bearing mixtures.
 51. The method of claim 50 wherein said silicon oxide-bearing compound is selected from the group consisting of aluminosilicates, alkali silicates, alkaline earth silicates, alkali aluminosilicates, alkaline earth aluminosilicates, borosilicates, cadmium silicates, cobalt silicates, erbium silicates, iron silicates, lead silicates, manganese silicates, neodymium silicates, nickel silicates, yttrium silicates, ytterbium silicates, zinc silicates, zircon, and mixtures thereof.
 52. The method of claim 48 wherein aA_(b)X_(w).N_(d)X_(z) , is selected from the group consisting of calcium oxide-bearing compounds, calcium oxide-bearing solid solutions, and calcium oxide-bearing mixtures.
 53. The method of claim 52 wherein said calcium oxide-bearing compound is selected from the group consisting of calcium alkalisilicates, calcium aluminates, calcium aluminosilicates, calcium alkalialuminosilicates, calcium bismuthates, calcium borates, calcium cerates, calcium chromites, calcium cuprates, calcium ferrites, calcium gadolinium oxides, calcium gallates, calcium germanates, calcium hafnate, calcium manganates, calcium molybdates, calcium niobates, calcium phosphates, calcium plumbates, calcium silicates, calcium stannates, calcium sulfates, calcium tantalates, calcium titanates, calcium tungstates, calcium uranium oxides, calcium vanadates, calcium yttrium oxides, calcium zirconates, and mixtures thereof.
 54. The method of claim 40 wherein said first chemical reaction is an oxidation-reduction reaction of the following type: yA+aM_(x)O_(y)=>yAO_(a)+axM where A is an elemental reactant, M_(x)O_(y) is an oxide constituent of the said at least one synthetic microtemplate, AO_(a) is an oxide first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said intermediate microcomponent, and M is a second reaction product; and wherein a, x, and y are stoichiometric coefficients.
 55. The method of claim 54 wherein AO_(a), is selected from the group consisting of solid oxide compounds, oxide solid solutions, and solid oxide mixtures.
 56. The method of claim 54 wherein AO_(a), is selected from the group consisting of silicon oxide-bearing compounds, silicon oxide-bearing solid solutions, and silicon oxide-bearing mixtures.
 57. The method of claim 56 wherein said silicon oxide-bearing compound is selected from the group consisting of aluminosilicates, alkali silicates, alkaline earth silicates, alkali aluminosilicates, alkaline earth aluminosilicates, borosilicates, cadmium silicates, cobalt silicates, erbium silicates, iron silicates, lead silicates, manganese silicates, neodymium silicates, nickel silicates, yttrium silicates, ytterbium silicates, zinc silicates, zircon, and mixtures thereof.
 58. The method of claim 54 wherein AO_(a), is selected from the group consisting of calcium oxide-bearing compounds, calcium oxide-bearing solid solutions, and calcium oxide-bearing mixtures.
 59. The method of claim 58 wherein said calcium oxide-bearing compound is selected from the group consisting of calcium alkalisilicates, calcium aluminates, calcium aluminosilicates, calcium alkalialuminosilicates, calcium bismuthates, calcium borates, calcium cerates, calcium chromites, calcium cuprates, calcium ferrites, calcium gadolinium oxides, calcium gallates, calcium germanates, calcium hafnate, calcium manganates, calcium molybdates, calcium niobates, calcium phosphates, calcium plumbates, calcium silicates, calcium stannates, calcium sulfates, calcium tantalates, calcium titanates, calcium tungstates, calcium uranium oxides, calcium vanadates, calcium yttrium oxides, calcium zirconates, and mixtures thereof.
 60. The method of claim 54 wherein said second reaction product, M, is selected from the group consisting of a solid metal, a solid metal alloy, a solid intermetallic compound, a solid metallic mixture, a solid intermetallic mixture, and mixtures thereof.
 61. The method of claim 40, wherein said chemical reaction is selected from the group consisting of an additive reaction of the following type: aA_(b)Y_(c)+M_(d)X_(e)=>aA_(b)Y_(c).M_(d)X_(e) where A_(b)Y_(c) is a reactant, M_(d)X_(e) is a constituent of the said at least one synthetic microtemplate, and aA_(b)Y_(c).M_(d)X_(e) is an ionically or covalently bonded solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent; and wherein a, b, c, d, and e are stoichiometric coefficients; a metathetic reaction of the following type: aA_(b)X_(w)+M_(c)X_(y).N_(d)X_(z)=>aA_(b)X_(w).N_(d)X_(z)+M_(c)X_(y) where A_(b)X_(w) is a reactant, M_(c)X_(y) .N_(d)X_(z) is a constituent of the said at least one synthetic microtemplate, aA_(b)X_(w).N_(d)X_(y) is an ionically or covalently bonded first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said intermediate microcomponent, and M_(c)X_(y) is a second reaction product; and wherein a, b, c, d, w, y, and z are stoichiometric coefficients; and an oxidation-reduction reaction of the following type: yA+aM_(x)O_(y)=>yAO_(a)+axM where A is a reactant, M_(x)O_(y) is an oxide constituent of the said at least one synthetic microtemplate, AO_(a) is an oxide first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said intermediate microcomponent, and M is a second reaction product; and wherein a, x and y are stoichiometric coefficients; and combinations thereof.
 62. The method of claim 40 wherein said second chemical reaction is an additive reaction of the following type: aA_(b)Y_(c)+M_(d)X_(e)=>aA_(b)Y_(c).M_(d)X_(e) where A_(b)Y_(c) is a reactant, M_(d)X_(e) is a constituent of the said at least one synthetic microtemplate, and aA_(b)Y_(c).M_(d)X_(e) is an ionically or covalently bonded solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent; and wherein a, b, c, d, and e are stoichiometric coefficients.
 63. The method of claim 62 wherein aA_(b)Y_(c).M_(d)X_(e) is selected from the group consisting of solid oxide compounds, oxide solid solutions, and solid oxide mixtures.
 64. The method of claim 62 wherein aA_(b)Y_(c).M_(d)X_(e) is selected from the group consisting of silicon oxide-bearing compounds, silicon oxide-bearing solid solutions, and silicon oxide-bearing mixtures.
 65. The method of claim 64 wherein said silicon oxide-bearing compound is selected from the group consisting of aluminosilicates, alkali silicates, alkaline earth silicates, alkali aluminosilicates, alkaline earth aluminosilicates, borosilicates, cadmium silicates, cobalt silicates, erbium silicates, iron silicates, lead silicates, manganese silicates, neodymium silicates, nickel silicates, yttrium silicates, ytterbium silicates, zinc silicates, zircon, and mixtures thereof.
 66. The method of claim 62 wherein aA_(b)Y_(c).M_(d)X_(e) is selected from the group consisting of calcium oxide-bearing compounds, calcium oxide-bearing solid solutions, and calcium oxide-bearing mixtures.
 67. The method of claim 66 wherein said calcium oxide-bearing compound is selected from the group consisting of calcium alkali-silicates, calcium aluminates, calcium aluminosilicates, calcium alkali-aluminosilicates, calcium bismuthates, calcium borates, calcium cerates, calcium chromites, calcium cuprates, calcium ferrites, calcium gadolinium oxides, calcium gallates, calcium germanates, calcium hafnate, calcium manganates, calcium molybdates, calcium niobates, calcium phosphates, calcium plumbates, calcium silicates, calcium stannates, calcium sulfates, calcium tantalates, calcium titanates, calcium tungstates, calcium uranium oxides, calcium vanadates, calcium yttrium oxides, calcium zirconates, and mixtures thereof.
 68. The method of claim 40 wherein said second chemical reaction is a metathetic reaction of the following type: aA_(b)X_(w)+M_(c)X_(y).N_(d)X_(y)=>aA_(b)X_(w).N_(d)X_(y)+M_(c)X_(y) where A_(b)X_(w) is a reactant, M_(c)X_(y).N_(d)X_(y) is a constituent of the said intermediate microcomponent, aA_(b)X_(w).N_(d)X_(y) is an ionically or covalently bonded first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent, and M_(c)X_(y) is a second reaction product; and wherein a, b, c, d, w, y, and z are stoichiometric coefficients.
 69. The method of claim 68 wherein aA_(b)X_(w).N_(d)X_(z), is selected from the group consisting of oxide compounds, oxide solid solutions, and oxide mixtures.
 70. The method of claim 68 wherein aA_(b)X_(w).N_(d)X_(z), is selected from the group consisting of silicon oxide-bearing compounds, silicon oxide-bearing solid solutions, and silicon oxide-bearing mixtures.
 71. The method of claim 70 wherein said silicon oxide-bearing compound is selected from the group consisting of aluminosilicates, alkali silicates, alkaline earth silicates, alkali aluminosilicates, alkaline earth aluminosilicates, borosilicates, cadmium silicates, cobalt silicates, erbium silicates, iron silicates, lead silicates, manganese silicates, neodymium silicates, nickel silicates, yttrium silicates, ytterbium silicates, zinc silicates, zircon, and mixtures thereof.
 72. The method of claim 68 wherein aA_(b)X_(w).N_(d)X_(z), is selected from the group consisting of calcium oxide-bearing compounds, calcium oxide-bearing solid solutions, and calcium oxide-bearing mixtures.
 73. The method of claim 72 wherein said calcium oxide-bearing compound is selected from the group consisting of calcium alkalisilicates, calcium aluminates, calcium aluminosilicates, calcium alkalialuminosilicates, calcium bismuthates, calcium borates, calcium cerates, calcium chromites, calcium cuprates, calcium ferrites, calcium gadolinium oxides, calcium gallates, calcium germanates, calcium hafnate, calcium manganates, calcium molybdates, calcium niobates, calcium phosphates, calcium plumbates, calcium silicates, calcium stannates, calcium sulfates, calcium tantalates, calcium titanates, calcium tungstates, calcium uranium oxides, calcium vanadates, calcium yttrium oxides, calcium zirconates, and mixtures thereof.
 74. The method of claim 40 wherein said second chemical reaction is an oxidation-reduction reaction of the following type: yA+aM_(x)O_(y)=>yAO_(a)+axM where A is a reactant, M_(x)O_(y) is a constituent of the said intermediate microcomponent, AO_(a) is an oxide first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent, and M is a second reaction product.
 75. The method of claim 74 wherein AO_(a), is selected from the group consisting of solid oxide compounds, oxide solid solutions, and solid oxide mixtures; and wherein a, x, and y are stoichiometric coefficients.
 76. The method of claim 74 wherein AO_(a), is selected from the group consisting of silicon oxide-bearing compounds, silicon oxide-bearing solid solutions, and silicon oxide-bearing mixtures.
 77. The method of claim 76 wherein said silicon oxide-bearing compound is selected from the group consisting of aluminosilicates, alkali silicates, alkaline earth silicates, alkali aluminosilicates, alkaline earth aluminosilicates, borosilicates, cadmium silicates, cobalt silicates, erbium silicates, iron silicates, lead silicates, manganese silicates, neodymium silicates, nickel silicates, yttrium silicates, ytterbium silicates, zinc silicates, zircon, and mixtures thereof.
 78. The method of claim 74 wherein AO_(a), is selected from the group consisting of calcium oxide-bearing compounds, calcium oxide-bearing solid solutions, and calcium oxide-bearing mixtures.
 79. The method of claim 78 wherein said calcium oxide-bearing compound is selected from the group consisting of calcium alkalisilicates, calcium aluminates, calcium aluminosilicates, calcium alkalialuminosilicates, calcium bismuthates, calcium borates, calcium cerates, calcium chromites, calcium cuprates, calcium ferrites, calcium gadolinium oxides, calcium gallates, calcium germanates, calcium hafnate, calcium manganates, calcium molybdates, calcium niobates, calcium phosphates, calcium plumbates, calcium silicates, calcium stannates, calcium sulfates, calcium tantalates, calcium titanates, calcium tungstates, calcium uranium oxides, calcium vanadates, calcium yttrium oxides, calcium zirconates, and mixtures thereof.
 80. The method of claim 74 wherein said second reaction product, M, is selected from the group consisting of a solid metal, a solid metal alloy, a solid intermetallic compound, a solid metallic mixture, a solid intermetallic mixture, and mixtures thereof.
 81. The method of claim 40, wherein said chemical reaction is selected from the group consisting of an additive reaction of the following type: aA_(b)Y_(c)+M_(d)X_(e)=>aA_(b)Y_(c).M_(d)X_(e) where A_(b)Y_(c) is a reactant, M_(d)X_(e) is a constituent of the said at least one synthetic microtemplate, and aA_(b)Y_(c).M_(d)X_(e) is an ionically or covalently bonded solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent; and wherein a, b, c, d, and e are stoichiometric coefficients; a metathetic reaction of the following type: aA_(b)X_(w)+M_(c)X_(y).N_(d)X_(z)=>aA_(b)X_(w).N_(d)X_(z)+M_(c)X_(y) where A_(b)X_(w) is a reactant, M_(c)X_(y).N_(d)X_(z) is a constituent of the said intermediate microcomponent, aA_(b)X_(w).N_(d)X_(z) is an ionically or covalently bonded first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent, and M_(c)X_(y) is a second reaction product; wherein a, b, c, d, w, y, and z are stoichiometric coefficients; and an oxidation-reduction reaction of the following type: yA+aM_(x)O_(y)=>yAO_(a)+axM where A is a reactant, M_(x) O_(y)is an oxide constituent of the said intermediate microcomponent, AO_(a) is an oxide first solid reaction product that is a solid compound, a solid solution, or a solid mixture that is retained in the said shaped microcomponent, and M is a second reaction product; and wherein a, x, and y are stoichiometric coefficients; and combinations thereof.
 82. The method of claim 40, wherein said shaped microcomponent defines a space wherein said space is provided with at least one additional non-native substance.
 83. The method of claim 82, wherein said at least one additional non-native substance is a pharmaceutically active substance.
 84. The method of claim 40 wherein said shaped microcomponent possesses a shape selected from the group consisting of a solid microcylinder, a microtube, a solid microbar, a hollow microbar, a solid microsphere, a hollow microsphere, a microwheel, a microgear, a microrotor, a microplate, a microdisk, a microtetrahedron, a microwedge, a microtetrakaidecahedron, a microspring, a microspiral, a microlever, a microcantilever, a solid microcone, a microfunnel, a microhoneycomb, and a micromesh.
 85. The method of claim 40 wherein said shaped microcomponent is used in a device selected from the group consisting of a micropump, a microvalve, a microfunnel, a micronozzle, a microreactor, a microbearing, a micropulley, a microturbine engine, a micropiston engine, a micromotor, a microactuator, a microswitch, a microtransducer, a microhinge, a microrelay, a microdie, a microsensor, a microcatalyst, a microsyringe, a microneedle, a microcapsule, a microsieve, a microfilter, a micromembrane, a microseparator, a micromirror, a microlens, a microprism, a microdiffraction grating, and a microrefraction grating.
 86. The method of claim 40 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 1 millimeter in size.
 87. The method of claim 40 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 100 microns in size.
 88. The method of claim 40 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 25 microns in size.
 89. The method of claim 40 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 10 microns in size.
 90. The method of claim 40 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 1 micron in size.
 91. The method of claim 40 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 100 nanometers in size.
 92. The method of claim 40 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 25 nanometers in size.
 93. The method of claim 40 wherein said shaped microcomponent possesses at least one dimensional feature that is less than 10 nanometers in size.
 94. A shaped microcomponent made in accordance with the method of claim
 40. 95. A shaped microcomponent derived in accordance with the method of claim 40 from an article having an original chemical composition and an original dimensional feature, said original chemical composition having been converted to an altered composition while retaining said original dimensional feature. Method of Microforming a Microarticle of Silicon Followed by Chemical Conversion to Ceramic
 96. A method of producing a ceramic microarticle, said method comprising: (a) obtaining a silicon microarticle having a target shape; (b) subjecting said microarticle to a process so as to converting at least some of said silicon to silica; (c) subjecting said silica to a process so as to convert at least some of said silica to a ceramic-bearing microartcile having a chemical composition different than said silicon microarticle and different than silica while substantially maintaining said target shape.
 97. A method according to claim 96 wherein said silicon microarticle is prepared from a method selected from the group consisting of photolithography, dry physical etching, ion etching/sputtering, laser ablation, dry chemical etching, combined dry physical and chemical etching, wet chemical etching and LIGA. Method of Microforming a Microarticle of Silicon Followed by Coating with Silica Followed by Chemical Conversion to Ceramic-Bearing Microarticle
 98. A method of producing a ceramic microarticle, said method comprising: (a) obtaining a silicon microarticle having a target shape; (b) providing a silica-bearing coating on said microarticle, said coating comprising silica; and (c) subjecting said silica to a process so as to convert at least some of said silica to ceramic-bearing microarticle while substantially maintaining said target shape.
 99. A method according to claim 98 wherein said silicon microarticle is prepared from a method selected from the group consisting of photolithography, dry physical etching, ion etching/sputtering, laser ablation, dry chemical etching, combined dry physical and chemical etching, wet chemical etching and LIGA.
 100. A method according to claim 98, wherein said silicon microarticle is provided with a coating with a method selected from the group consisting of physical or chemical vapor deposition, spin coating of a silica slurry or silica precursor solution, screen printing of silica slurry or silica precursor solution, pressing of hot viscous glass onto the silicon microarticle, and casting of molten glass onto the silicon microarticle.
 101. A method according to claim 40 wherein said first reaction includes the oxidation of silicon. Method of Microforming a Microarticle of Silicon Followed by Chemical Conversion to Silicon-bearing Ceramic Precursor Compound
 102. A method of producing a ceramic microarticle, said method comprising: (a) obtaining a silicon microarticle having a target shape; (b) subjecting said microarticle to a process so as to converting at least some of said silicon to silicon-bearing ceramic precursor compound.
 103. A method according to claim 102 wherein said silicon-bearing ceramic precursor compound is selected from the group consisting of carbides, nitrides, borides and MoSi2 compounds.
 104. A method according to claim 102 wherein said silicon-bearing ceramic precursor compound is selected from the group consisting of intermetallic compounds.
 105. A method according to claim 102 further comprising (c) subjecting said silicon-bearing ceramic precursor compound to a process so as to convert at least some of said silicon-bearing ceramic precursor compound to a ceramic.
 106. A method according to claim 102 further comprising (c) subjecting said silicon-bearing ceramic precursor compound to a process so as to convert at least some of said silicon-bearing ceramic precursor compound to an intermetallic compound.
 107. A method according to claim 102 wherein said silicon microarticle is prepared from a method selected from the group consisting of photolithography, dry physical etching, ion etching/sputtering, laser ablation, dry chemical etching, combined dry physical and chemical etching, wet chemical etching and LIGA. Method of Microforming a Microarticle of Silicon Followed by Coating with Silica Followed by Chemical Conversion to Ceramic
 108. A method of producing a ceramic microarticle, said method comprising: (a) obtaining a silicon microarticle having a target shape; (b) providing a coating on said microarticle, said coating comprising a silicon-bearing ceramic precursor compound; and (c) subjecting said silicon-bearing ceramic precursor compound to a process so as to converting at least some of said silicon-bearing ceramic precursor compound to a material selected from the group consisting of ceramic and intermetallic compounds while substantially maintaining said target shape.
 109. A method according to claim 108 wherein said silicon ceramic precursor compound is selected from the group consisting of carbides, nitrides, borides and MoSi2 compounds.
 110. A method according to claim 108 wherein said silicon microarticle is prepared from a method selected from the group consisting of photolithography, dry physical etching, ion etching/sputtering, laser ablation, dry chemical etching, combined dry physical and chemical etching, wet chemical etching and LIGA.
 111. A method according to claim 108, wherein said microarticle is provided with a coating with a method selected from the group consisting of physical or chemical vapor deposition, spin coating of a silica slurry or silica precursor solution, screen printing of silica slurry or silica precursor solution, pressing of hot viscous glass onto the silicon microarticle, and casting of molten glass onto the silicon microarticle. 